Police Backup

As the title suggests, the backup units.

I apologize if this should be posted elsewhere, but is there a way to edit the backup units or have them alternate in what car they're responding in? Obviously you can within the selection screen of the setup process of LSPDFR can choose what car you want, be it the Buffalo, Stanier, Granger, etc, etc. But is there a way during Pursuits have the backup units respond in different cars? I never see any of the LSPD cops' respond in the Police interceptor, never do I see the Sheriffs respond in the Sheriff Granger, nor do I ever see the Park Ranger units come into effect if you're in that particular part of the map. It's always the same identical units, a plethora of Staniers and a few Buffalo's here and there. I guess what I'm saying is, is there a way to make the backup more like the actual wanted level system built in the game when the Police chase you? Minus the SWAT, unless you call for that.

I remember a mod in which it changed the Sheriff units in particular, forgot what it was but I believe it changed the dispatch.meta file and it made it so the Sheriff Staniers turned into Sheriff Interceptors, however unfortunately it never spawned Sheriff Grangers' as backup units, just the interceptors much like the LSPD interceptors. I also believe if I remembered correctly that there is a file that dictates the spawn ratio of what cars come into effect, as in 30 percent chance that the Police Buffalo spawns, 50 percent chance the Police Stainer spawns, so on and so fourth. I've combed through a lot of GTA 5's files, but no avail have I been able to figure it out or find the files to tinker with to see if it does anything. 

Any help would be great!